The present invention generally relates to the field of computer boards and BGA IC packages, and particularly to a way to fit/retrofit a BGA package with an improved heat transfer mechanism between the BGA package and the printed circuit board (PCB) it is mounted on.
Solder bonds are often used to attach integrated circuit (IC) packages to printed circuit boards. The printed circuit boards are specially designed for specific IC packages. The designer must pay close attention to various details such as signal propagation, power and ground routing, and heat dissipation. The printed circuit boards need to transmit signals along conductors fabricated in layers throughout the board in which signals may cross layers through vias. Power and ground planes also exist in the printed circuit board. A known method of attaching an IC to a printed circuit board involves the use of an array of solder balls, i.e., a ball grid array (BGA). The IC package is electrically connected with and mechanically bound to a printed circuit board by heating the assembly until the solder balls of the array flow to connect to terminals on the printed circuit board. Thus, the IC package is connected to its corresponding custom designed substrate or circuit board.
To enhance heat dissipation, a heat sink may be placed on the top air surface of the BGA package.
The increasing miniaturization in the semiconductor industry is presenting a set of challenges for the IC packaging industry. With ever increasing capability on ever smaller substrates and the fierce competition in the industry, it is necessary for new package technology development to contain costs. Therefore, the thermal, electrical, mechanical, and assembly characteristics of each IC package design must be optimally tailored.
A need exists for retrofitting PCB components with heat dissipation devices to improve circuit performance.
Also, as components become increasingly miniaturized, there is a need for a heat dissipation structure which does not take up additional volume beyond the PCB and its component parts.
Additionally, there is a need for enhanced secondary mechanisms to support heat transfer away from the package and IC die of emerging packages and die inside with increased power usage which already have a primary heat radiation mechanism.
Therefore, it would be desirable to provide an improved way to transfer heat from BGA packages and die within them to the PCB on which they are mounted on.
Accordingly, the present invention is directed to a heat dissipation structure for an integrated circuit package. In a first aspect of the present invention, a heat dissipation structure is disclosed for an electronic component mounted on a printed circuit board, comprising a thermally conductive layer with receptacles for holding a thermally conductive flowable material, the heat dissipation structure being placed between the electronic component and the printed circuit board.
In a second aspect of the invention, an arrangement of components is disclosed, comprising, in the following order, a primary heat sink, an integrated circuit package, a secondary heat sink, and a printed circuit board.
In the present invention, under the integrated circuit package, the heat sink uses hemispherical balls on the package side of a high heat conductive plate to improve heat transfer from the die or integrated circuit, especially, BGA, substrate to PCB power planes for heat dissipation.
The present invention leads to improved secondary heat transfer from IC die in BGA packages to the heat spreader power planes in the system PCB.
The present invention provides a heat dissipation structure which does not take up additional volume beyond the PCB and its component parts.
The present invention allows either retrofitting of the heat transfer mechanism or attachment during assembly.
It is to be understood that both the forgoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate an embodiment of the invention and together with the general description, serve to explain the principles of the invention.